1. Field of Invention
The present invention relates generally to telecommunications. More particularly, the present invention relates to communications network equipment, including hardware and software for implementing non-disruptive software upgrades, for implementing software version fallback, and for implementing distributed software upgrades of communicating network equipment with central control.
2. State of the Art
Current methods of upgrading software in communications networks involves the disruption of customer data for relatively long periods of time (e.g., up to ten hours, depending upon network topology and stability), as the network equipment is shut down for customer data and is configured to receive software from a remote controller over the network. During the software upgrade, if there is a sudden network disturbance, it is possible that certain portions of the network may be isolated. In these situations, if the download sequence is continued, different network regions may end up running potentially incompatible software versions, resulting in the partial inoperability of the network. Even if there is no network disturbance, once a software upgrade of a communications network equipment is complete, the only mechanism for reverting to a previous version of the software is to perform a similar disruptive "upgrade" with the previous version. Thus, the current methods of upgrading software in communications networks can be seen to have serious drawbacks.